152 TRICHOLOGIA MAMMALIUM; 
The fat (says this author) may be extracted by boiling the hair in alcohol; and is, ordi- 
narily, acid, (the margaric and oléic.) Lt has a blood-red tinge in red hair; greyish-grey 
in brown hair, and (according to Jahn’s, in Der Haarartz, ti. p. 49,) white hair* has a 
limpid oil. 
After the extraction of the fat, brown hair becomes greyish-yellow, and then behaves 
like horn. 
Hair is insoluble in water, whether cold or hot; but in Papin’s Digester is dissolved 
(all except the fat) with a disengagement of sulphuretted hydrogen. ‘lhe residue of the 
liquid, after evaporation, is viscous, and capable of being re-dissolved in water, when it 
does not become a jelly. From its watery solution a precipitate may be thrown down by 
concentrated acids—by chlorine—by the sub-acetate of lead, and by tannic acid. 
When hair is dissolved in concentrated acids (particularly by the nitric) the colored oils 
separate, coagulate by cold, and become limpid 
Chlorine whitens hair and produces, by its combination with it, a viscous transparent 
mass, which has a bitter taste, and dissolves in water and alcohol. Caustic potash, 
diluted, dissolves hair entirely. 
Hair may be dyed, melted and distilled —Wair may be colored by the metallic salts—both 
nitrate and sulphate; nitrate of silver blackens it When heated, hair melts, exhaling an 
odor of horn. It burns with a sooty flame, leaving a bloated coal. 
Upon dry distillation, hair gives off one-fourth of its weight of a carbon difficult to 
incinerate, the products being empyreumatic oil, water charged with ammonia, and com- 
bustible gases which contain sulphuretted hydrogen. 
Van Laer is of opinion, that hair consists, essentially, of a substance nearly allied to 
gelatine and bisulphuret of proteme.t This substance has the formula of carbon, 13; 
hydrogen, 10; nitrogen, 3; oxygen, 5, and gluttin (which is the form of gelatine which is 
obtained from the skin, from serous membrane, from hoof, from bone, from tendon, and 
from cartilage,) having the formula of carbon, 13; hydrogen, 10; nitrogen, 2, and 
oxygen, 5. 
There have also been found in hair silica, iron and manganese. 
The elements of Pile in the blood and in the milk.—'That the blood contains all the 
elements of hair, is found by its beg produced on the foetus; and that the mother’s milk 
is equal, in this respect, is demonstrated by the growth of the hair while a child is receiv- 
ing no other nourishment. P 
The ancient practice of milking the ewes, to make butter-cheese, was believed to have 
injured the growth of the lamb’s wool. (See Lib. of Use. Knowl. p. 48.) 
Or EXaMINING Pite.—It often becomes necessary, while examining a hair under the 
microscope, to turn it over and back again, or half way over—a task not easily performed. 
* He here speaks of white (albinos) hair, and not grey (colorless) hair, as we venture to presume. 
7 Proteine is the name giyen to the substance which enters into the three important animal compounds, albumin, fibrin, 
and cassin. 
